The PDI-03 is the legendary predecessor to the PGA-04 Speaker Simulator. It is a re-issue of the early 90's model with the "battleship grey" housing and metal knobs. The Palmer Speaker Simulator PDI-03 is a combined signal splitter, DI-box, and (when used as a load box) power soak. It comes in a single space rackmount unit. Especially designed for electric guitars and basses, all functions have been optimized for live and studio use.

The unit is directly connected to the speaker output of an amplifier, eliminating the need to mic up a speaker cabinet. With the built in 8 ohm load circuit, you can also use the PDI-03 without a speaker cabinet. The special filters within the simulator provide carefully contoured equalization. The signal from the unit is fed via a balanced XLR connector or unbalanced ¼" jack into a mixing console, tape deck, or power amplifier, etc. Amplifiers, particularly valve amps, can be driven really hard (into saturation) without being limited by volume. Amplifier noise and hum are greatly reduced to practically inaudible levels. Four parallel, unfiltered outputs are available to drive effects units.

The PDI-03 is a very simple to use piece of equipment. Two switches select between 6 filter presets enabling the unit to simulate various types of speakers and enclosures.

Low frequencies are affected by the three-way DEEP/NORMAL/FLAT switch. In FLAT position the sound is characteristic of an open-back 2 x 12 cabinet. The DEEP position reproduces the typical punch of a 4 x 12 stack.

The high end is affected by a three-way switch, MELLOW/NORMAL/BRIGHT. When using a heavily overdriven amp, the MELLOW position produces the warm singing "American" sound, whereas the NORMAL position has the bite of the classic "British" loudspeaker. In BRIGHT position, the top end is enhanced lending edge to lead guitar solos and brightness to rhythm parts. Spectacular sounds can be produced by mixing the dry FILTER OUTPUT with the LINE OUTS driving effects units.